單項選擇題

11. public void addStrings(List list) { 
12. list.add(”foo”); 
13. list.add(”bar”); 
14. } 
What must you change in this method to compile without warnings?() 

A. add this code after line 11: list = (List) list;
B. change lines 12 and 13 to: list.add(”foo”); list.add(”bar”);
C. change the method signature on line 11 to: public void addStrings(List< extends String> list) {
D. change the method signature on line 11 to: public void addStrings(List< super String> list) {
E. No changes are necessary. This method compiles without warnings.

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